Koshi no Kanbai is Japan's most famous and sought-after sake. Its "winter plum" label is familiar to enthusiasts everywhere, conjuring up the image of a sake so perfect that every single molecule seems immaculately in place.

Even in the early postwar years, Shogo Ishimoto's knack for making exceptional sakes was apparent. Totally focussed on his vision of sake excellence, he had produced a ginjo sake in 1946, an incredible extravagance at a time when both rice and sake were being rationed. Earning the respect of the sake mandarins in the Tax Ministry, the Ishimoto brewery was among 200 selected for special technical assistance by the National Research Institute of Brewing in 1950, leading to further improvements in equipment and technique.

In the 1960s, the sake trade was completely dominated by big breweries in Kobe and Kyoto, and regional breweries had almost no distribution outside their home prefectures. This changed when, after years of effort by Ishimoto's agent and friend, Eiji Maeda, occasional mentions of the astonishing sake from Niigata began to appear in the Tokyo newspapers. A prominent national politician discovered it. The Ginza clubs began to place orders. Before long, demand was so great that dozens of other regional labels were able to enter the Tokyo market,and the "Sake Boom" of the early 1970s got well and truly underway.

Many people are content to buy Koshi no Kanbai because of its name value. That's a shame, for the daiginjo, ginjo and junmai labels take sake brewing technique to the limit and sometimes beyond. It is very difficult to find words to describe a sake like "Chotokusen," the brewery's rare daiginjo label, which seems to elude all efforts to categorize it. "Appreciating this complex sake is more in the nature of an intellectual exercise," wrote one critic. "Each taste asks the sake drinker more questions than it answers."